This year, Dr. Sue Sisley became the only researcher in the U.S. to win federal approval for medical marijuana research. Last week, she lost her job.

Sisley, an assistant professor at the University of Arizona, intended to study the effects of cannabis on PTSD. After years of working with veterans who'd failed to treat their symptoms with FDA-approved drugs, but sang weed's praises, she'd become convinced that it might work.

In time, her office became a pseudo-confessional for former soldiers who'd turned to the black market for medicine. "Veterans were having the courage to tell me they were using this plant to successfully treat the whole constellation of symptoms," says Sisley. "After 10 years, I couldn't ignore it."

Convinced by the fact that these "highly principled" men and women were actively choosing to break the law, Sisley set out to gather objective data that might corroborate their anecdotal evidence. Her game plan: a triple-blind randomized control trial of marijuana's effect on 70 veterans with PTSD.

Sisley was one of only 15 people over the last 20 years to complete the arduous federal approval process for cannabis research, and the University's sudden decision to fire her effectively makes it impossible to carry out her work.

Several conservative Arizona lawmakers have attempted to block cannabis studies in the state, and in recent months, Sisley says, the university has been uncooperative in moving her research along:

"The University of Arizona can say whatever they want about their love of pot research but the proof is in their inaction, not their words."

But even more than the university, it's the lawmakers behind them that Sisley holds responsible. "These hyper-conservative lawmakers in Arizona are fundamentally opposed to marijuana research," she says. "Some have even gone on record with reporters to say weed research is a strategy for achieving marijuana legalization. They don't want to see any universities resources going to support this work."

It's unclear why exactly Sisley was fired — the University of Arizona told the Daily Beast it "does not comment on personnel issues" — but her termination means that veterans suffering from the psychic horror of PTSD, who may have benefitted from a more thorough understanding of pot's effects, will have to stick to Zoloft and Paxil for now. Her attorney plans to file a formal appeal.